Privacy

Karuta works without an account: if you do not sign in, your decks and your progress stay on the phone and no personal data leaves the device.

If you do sign in, an account and a copy of your data in the cloud are needed to find them again elsewhere and for the community side. There is no advertising, no profiling, and data is never sold or handed to third parties for commercial purposes.

The data controller is Riccardo Senes, a private individual resident in Italy. Karuta is an individual project: there is no company behind it, and the controller is the person who writes it.

For any request about your data you can write to support.karuta@gmail.com.

Only what is needed to run the things you asked for. In detail:

• Account. Sign-in happens through Google. Karuta receives an identifier and the associated email address, and never has your password.
• Public profile. Username, display name, biography and avatar, if you fill them in. The avatar is not a photograph: it is a text description of a drawn face, generated on the device.
• Published content. The decks you choose to publish, their cards, and any images. They are public by definition, along with the username of whoever published them.
• Your connections. Who you follow, who follows you, and pending follow requests.
• Community activity. Votes, favourites and reports you send.
• Study summary. Streak, cards reviewed, days studied and retention. They feed the challenge feature and are visible only to people who have an accepted follow with you, in either direction.
• Study data. Reviews, progress and statistics. They live on the device and, if you signed in, are synchronised.
• Notifications. If you turn them on, a device identifier supplied by Google is stored, which is what makes delivery possible. It identifies the app installation, not you, and is removed when you sign out.
• Anything you write to us. If you use Settings, Leave feedback, the app opens your own mail program with a message already filled in, including the app version and device model. Sending it is your decision: the app sends nothing by itself.
• Diagnostics. When something crashes the app sends a technical report: device model, system version and the error trace. Sending personal data is switched off in the configuration.

• No location, no contacts, no microphone, no camera. Photo access is requested only if you choose to put an image on a card, one file at a time, and you can refuse.
• No ad network, no advertising identifier, no analytics or tracking across other apps or sites.
• No payment data. Card numbers and billing details never pass through Karuta: they are handled by the payment service you use. Karuta only receives confirmation that a subscription is active.

• Account, profile, published decks and synchronised data: Supabase, Central EU (Frankfurt) region.
• Card images: Cloudflare R2, Western Europe region. Two things need saying in full: the store is read from a public address, so anyone holding an image's address can see it, even when the card is not published. The address contains random identifiers, though, so it is neither stumbled upon nor guessed.
• Crash reports: Sentry, in Germany.
• Notifications and purchases: Google, under their own policies.

Account data stays for as long as the account exists. When you delete it, the data is erased, including any images you uploaded. Signing out is a different thing: it removes the session from the device, but your cloud data stays where it is.

Three practical exceptions remain: decks somebody else has already imported carry on living on their device, because at that point they are their copy; crash reports, which contain no personal data, follow Sentry's own retention; and moderation records may be kept for as long as it takes to keep the community clean.

You can ask to access your data, correct it, delete it, or receive a copy. Two of those you can do yourself, right now, from the app:

• Deletion: Settings, Danger zone, Delete account. It is immediate and irreversible: it erases the cloud data, the published images and the local copy.
• A copy of your data: Settings, Export all decks. You get your content in a file.
• For anything else, write to support.karuta@gmail.com.

If you believe your data is being handled improperly, you can also lodge a complaint with the authority that supervises privacy in your country. In Italy that is the Garante per la protezione dei dati personali.

Karuta is not aimed at children and does not knowingly collect data from anyone under sixteen. If you notice that it has happened, write to support.karuta@gmail.com and we will erase it.

All network traffic runs over encrypted connections. Session credentials live in the device's secure storage, not in an ordinary file.

No system is a hundred per cent secure, and anyone claiming otherwise is overstating it. Reasonable measures are taken, and that is what can honestly be promised.

The providers listed above keep the data in Europe. Some of them, in order to operate, may also process it on servers in other countries: where that happens, the safeguards required by European law for transfers outside the Union apply.

If this document changes in any substantial way, the date at the top changes with it and the change is flagged in the app. Earlier versions stay available on request.